Method of making party-colored screens for use in color photography.



` UNITED STATES PATENT oE-EioE.

CHARLES L. A. BRAss'E-UE, ior ORANGE-NEW JERSEY.

METHOD or :MAxINe'PAETY-COEREE SCREENS Eon USE 1N fc'o'LoE Enforcement 1,081,484. s ,pem'sanbfLatesrateaf. Patenteanec. 16,1913:

. .nppucgtrionmeauugustao,1909. sex-inmensas.

V Toallfwhom t may concern.' l grained. But it is evident that absolute Be 1t known that I, CHARLEs L. A.'BRAS -f jperfection" if color ,canv only be obtained sEuR, a citizenofthe AIliiited States, and a- :when the patterny is so' fine and s ofneail, resident of Orange, ntherouiity of Essex regularly recurrent', th'at`the smallest `dta1-l 5 and State .0f New Jersey', .have inventedaoft'h'e negativecai' be reproduced incorrect 69 certain new' and useful Improvement" fcolor 'oi1`fth'e' positive." Thisineess ofpagti `Methods1of.MakingParty-Colored:Screens tern and `IJerie'ction of distribution is parfor Use in' Color Photography, of "which'the ',ticilarlj? necessary in thel case' of the'mo'ving following is a specification. 1 pictu'riindustry, where' the' details, owing 1o -The present inventionirelates toamethod 'to' 'thesmall 'sizeiof' the picture used, are 6@ .lof making party-colored vscreens for use in necessarily 'extremely' n'e. f l color photography, the primary object of "lfgrained sceens,"\ with thegrains pro-5 v the invention being to secure amore even or miscuously distributed be employed, it will uniform 'distribution ofthe different colored Ibe' very 'diflic'ult t' 'obtainl correct color syn# grains forming the screen. thesis 'of'jsma'll details', su'ch as an eye, as the 7g Another object is` to provide such screens grainlsfarwy'lliable lto bunch together in of any desired lengths and width for use in groups of one' color, and rains o f the nefces-` conjunction with films for moving picture saryc'olormay beentire y absent from the work. i y spot at'whicli they happento'b'e needed. Y Other objects will appear hereinafter. The method herein described is illustrated 75 Heretofore, partyecolored screens for use in'theaccoinpanying drawing",forming,partV in color-photography have been"made in hereof, in 'whichl' `regularly recurring patterns, and of Figflire'lisa partial'view in perspective l grains or dots promiscuouslydistributed showingthre'e sheets a, c united together; .y over .the surface cfa plate. Sub-divided Fig. 2 shows a slice from such a sheet in 80; photographs takenaccording to color measside and end elevations; Fig. 3 illustrates aA "j'urements and theory, require the use of two part voit' a block made from slices such as screensone for taking the negative, which shown-in Fig.` 2; Fig. 4 illustrates a slice` negative is' of itself colorless, and one for,V from a block such-'assllicw'n in'Fig. 3, mount# viewing the colorless positive printed by ,ed on a lilm or'supportpreparatory to thinf; 85 A, l contact from such anegative, and such posiningfdown the screen and Fig.`5 illustrates `"tives when viewed incombination with a 1tje formation of a long screen from a cir-xI viewing screen'in such a position that4 each rcular block. v colored area of the screen is exactly oppol. fAccor'ding to the present invention, I

85 site- `the corresponding color record-of the nform threadsor filaments of. the different 90 positive, may correctly represent all the colors required'and bunch them together 'colors of the original subject. It i's evident lengthwise, and compact them under suit,- not only that this'method is costly, but that able conditions by pressure. I then slice oil', vit canv onlybe used where' the material vemthin sheets, lcutting transversely to the 40 ployed as a supportfor` the screen and for .lengths of the threads orlilaments in the 95 the positive is rigidand not liable to distorslid block, as by a -veneer I n'achir'e.v But tion.- In the caseofroll filmslwllere thecel-` -with veneercuttin'g machines as` now built, -luloid ,or other' pliable supporting material .the sheet so"cut isfnot thin enou h as: it,v is liableV to distortion by' reason of unequal comes 'outf'o'f the machine.. TheA 'ickness contractionsit is impossible to employA this yr'n'ust` be reduced yby griridin or other 'ap- 190 method as thepatterns ofthe screen and v'of propriate'meansI until the lt ickness of the the positive can no longerl be made to match. sheet'be nov greater than the diameter of the Duplication from colored negatives,.that individual thread forming one of the' cole is, those in vwhich the photographic emulsion fored areas.l It will'be farYbetter, indeed to r is flowed directly )on the screen, is always havethe sheet muchthinner than th diam- 105 possible lby the Lmethod described in my ap' eter ,of such thread, since it is highly adplication filed February 28,1907, Serial No. `van'tageous that the Vcone of light coming 359,895, and that irrespective ol"y whether from the lensto a focus on a film shall be the pattern- 011 4the Screen. be' a lef-UllabllyA as` unimpeded as possible in its course recurrent one, as lines', or whether it be: through the colored area tothe underlying 110 lm. While the threads used in this process can be natural filaments or threads 'spun by methods analogous to those employed in producing artificial silk, I prefer to cut sheets of plastic material, as Celluloid, for example, into threads, as. a muchy greater regularity of section, and, therefore, of colored area, is obtained. The threads can be grouped in sets of three different colors' by winding ,them to ether; or, better still, three 'thin sheets of t ev plastic material can be cemented -together and then be cut into threads each thread showing a section of' three differently colored areas. If we now bunch these threads together lengthwise,

either the single threads, or the triple-COL.

ored threads, or threads woven of a greater number of groups of singleor triple threads, and press them together under appropriate conditions, we will obtain a solid block of plastic material which has only to be cut in a veneering machine, at right angles, or sub' stantially at right angles, to the direction of the threads to obtain sheets composed ofthe differently colored areas practically uniformly distributed. As above stated, grindingor other appropriate means may have to -be used to get suchsheets down to the-required thinness.

A cone of light coming to a focusvat a point near the principal optical axis w1ll go through unimpeded even if the colored areas be fairly thick, but along the margins of the photograph where the axis of the cone of llight strikes theA plate or film at an angle l' which may be as high as 45, and, in cases,

of very wide angle lenses, evenmore than thls, it is'evident that rays will be impeded 1n their courses unless the material forming the colored areas be extremely thin as compared to their width in the plane .of the screen.

' In my line screens, I had adopted a width of line of one five-hundred-and-twentieth of an inch (1/520) and a thickness of not `more than one twenty-five hundredth of anY inch (1/2500) and with some colors a thin- 'ness `assmall as one four-thousandth of an inch (1/4000). It is evident that, as sheets of such thinness cannot be obtained directly on a veneer-'ing machine, recourse must be had to grindlng or other means in order to 'reduce the thickness. Such reduction ofthe thlckness can be done after the sheet has 55 been. mounted ona supporting lm or plate to give it body. The supporting film may be colorless, or it may have incorporated in 1t the light orange color which is generally t used to equalize the times'of exposure under the three colors; in the latter case, when Working underl the sameconditions of light, 1t will be possible to obtain correctly colored negatwes without usinga separate orange coloredscreen at the lens.

If it is. desired to,k use threads ofother than taaie material, sieh as .artificial silk;

-Or entrainements ef any kiama 1S' only necessary to im"regnate the dyed material with a thinso ution of Celluloid or other cementing compound which will enable'the Athreads to form a solidblock when pressed together. 4This block can `be then veneered as in the former ease.

In case a material be used which cannot becompressed` sufficiently to obliterate all the spaces .between the threads, the inter l stices so remalnng must be filled vby a powder which will not dye the/threads but which will lill up such interstices and render them opaque to light; a powder, such as carbon may be added to the Celluloid used as a cement, or the opacity may be obtained .by chemical development after the sheets have been veneered. In that case, of course', one

of the necessary chemical elements must be `incorporated in the Celluloid used as a cement.

Referring to the drawing, three differently'v colored sheets a, b, o, are cemented together to form a thin compound sheet or veneer,

and this is sliced into tri-chromatic strings" as shown in Fig. 2, the several threads;

strings or strife being rectangular'in sectionfr and having sides as small as may be convenient, as, say, one one-thousandth of an inch (1/1000), which can be cut ywith such a thin sheet. These tri-colored strings are then gathered together and compacted by pressure, a suitable cement being used if necessary, to form a block B of suit-able size..

This block is then'shaved off across the ila' ments a, b, 0 to form as thin sheets as may be, such sheets beinga mosaic, as will be evident. sheets, which is done by mounting` them onsupports, as a plate or film d, as shown in Fig. 4,- and then grinding orotherwise thinning down to a point such as thatv indicated by the dotted line, Fig. 4, in which, it will vbe noted, the final thickness of the dots a,

The next step is to thin down lsuch stantially at righ-t angles to theplane of the film. Thereafter, the screen'is mounted on a film and is thinned down as above de-l scribed in connection with Fig/i. Afterward, the photographic emulsion is placed on the screen side of the film..

While I have mentioned the one onethousandth Y (1 /.1000) I of. an inch above, I

have done so merely as an exampleyI contemplate making the dots of as small dimensions as possible.

, In order to obtain screens long enough for usel in connection with films for moving picture work, a circular block may be built up of a plurality of sectors or truncated secdecrease in length as the dista-nce from the central radius of the sector increases, being out off in trimming a rectangularblook to form the sectors or truncated sectors.

What I claim as newand desire' to secure by Letters Patent .of the United States is l.. The method, substantially as herein set forth, of making party-colored screens for use in color photography, consisting in forming separate threads of different colors, compacting the same to form a brous block, cutting the block transversely of the threads to form a party-colored sheet, and thinning down said sheet to form the screen:

2. The method, substantially as herein setV` forth, of makinglong party-colored screens for use in conjunction with moving picture films in color photography, consisting in forming separate threads of different colors, compactingthe same to form blocks, forming fibrous sectors from said blocks, forming a circu ar block from said sectors, cutting the circular block circumferentially into a ribbon, and thinning down said ribbon.

3. The method, substantially las hereinbefore set forth, of making party-colored screens for use in color photography, consisting in forming threads of different colors,

comp-acting .the same to form a fibrous block, cutting the block transversely of the length of the threads to form a party-colored sheet, mounting said sheet on a compensating screen, and then thinning down said sheet to form the screen.

i 4. The method, substantially as hereinbei fore set forth, of making party-colored screens for unse in color photography,` consisting in forming threads of different colors, compacting the 'same into fibrous` blocks,

' forming sectors from said'bloc'ks with the threads of each -sector running in the direction of a radius thereof, forming a circular block from said sectors, cutting the circular block transversely of all the threads to form a ribbon, mountlngsaid ribbon on a comi pensating screen, and then thinning down saidribbon to form the color-sifter.

- 5.- 'lhe method, substantially as hereinbe-A partycolored threads fore set forth, of making partycolored screens for use in color photography, consisting in forming partycolored threads by into one thread, uniting a series. of such twisted threads into a Jnass havlng such threads lying substantially in one direction twisting three threads, each of its own color,

therein, and cutting said mass in a direction partycolored screen.

6. 'The method, substantially as hereinbefore set forth, of making partycolored screens for use in color photography, consisting in twisting togetherthree threads each of its own color to form a single partycolored thread, uniting a series of such at right angles to said direction to form a vpartycolored threads into one mass having Asuch threads lying in one direction therein,

cutting said mass at right angle to said direction to form a partycolored screen,and then thinning or grinding down said screen.

7. The method, substantially as hereinbefore set forth, of making partycolored sisting in twisting together three threads each of its wn color to form a single partycolored thread, uniting a series of such into sector-shaped screens for use in color photography, conmasses having the threads therein runningl parallel to a radius thereof, uniting said sector-shaped masses into a circular block,

and cutting said block spirally to form a continuous partycolored screen.

8. The method, substantially as hereinbefore set forth, of making partycolored screens for use-in color photography, consisting in twisting together three threads each of its own color to form a single part-ycolored thread, 4.uniting a l series of such partycolored threads into sectorfshaped masses having the threads therein running parallel to a radius thereof, uniting said sector-shaped masses into a circular block, cutting said block spirally to form a continuous partycolored screen-film, mounting the same upon a support, and thinning or grinding down said screen. Y

9. The method substantially as hereinbe fore set forth, in making party-colored screens. in color photography, consisting in forming threads of different colors, uniting a series of such party-colored threadsI into one mass having said threads lying in one direction therein, cutting said mass at right angles to said direction to form a partycolored screen, and then thinning or 'grinding down said screen until the thickness thereof is not greater than the diameter of an individual thread.

lO. The method substantially as hereinbefore set forth, in .making partycolored screens in color photography, consisting in forming threads of different colors, uniting 'aseries of such party-colored threads into "wie direction therein, cutting saidmass at right and State of New Jersey this 13th day of anlglesdto said diection Nilo form a part- August A. D. 1909. co ore screen, an then t innin or in v ,ing down said screen until th thness CHARLES L' A' BRASSEUR' I,5 thereof is less than the diameter' of @n in- Witnesses: v

diviolual thread. ANNA R. KLEHM,

Signed at .Orange in the county of Essex DYER SMITH. 

